tuberculosis%20-%20pulmonary
TUBERCULOSIS - PULMONARY
Tuberculosis (TB) suspect is any one who has signs or symptoms suggestive of TB (eg >2 weeks productive cough).
Definite TB is considered in patients with culture or molecular line probe assay positive for Mycobacterium tuberculosis, or in patients with at least 1 sputum smear positive for acid-fast bacilli.
TB cases are also classified based on the disease anatomical site, bacteriological results (including drug resistance), previous treatment history and patient's HIV status.
Pulmonary TB is a case of TB that involves the lung parenchyma.
Miliary TB is considered as PTB since lung lesions are also seen.
TB in the pleural effusion, mediastinal and/or hilar lymph nodes with no evidence of abnormalities in the chest x-ray are considered extrapulmonary TB.
Patients presenting with both PTB and extrapulmonary TB are classified as a case of PTB.

Monitoring

  • All patients should be monitored to assess response to treatment
  • Regular monitoring facilitates completion of treatment & permits identification & management of adverse reactions
  • Monthly monitoring of weight is important & will be the basis of dosage adjustment
  • Sputum smear exam is used to check response of patient to treatment
    • Sputum samples should be collected at each follow-up
    • Status of smear exam at the end of the intensive phase is a poor predictor of relapse
Sputum Smear Monitoring in New Pulmonary Tuberculosis (PTB) Patients
  • Sputum smear exam should be repeated at month 2, after the patient receives the last dose of intensive-phase treatment
  • If sputum smear is positive at month 2, sputum smear exam should be repeated at month 3
    • If negative, no further sputum monitoring is needed
  • If sputum smear is positive at month 3, culture & DST (line probe assay or Xpert MTB/RIF) should be done
    • Culture at this stage will detect resistance w/o waiting until the 5th month to change the regimen
    • Xpert MTB/RIF can detect Rifampicin resistance in sputum smear positive patients after >3 months
  • Treatment failure is considered if MDR-TB is detected (smear- or culture-positivity) at any point; change of treatment is recommended
Sputum Smear Monitoring in Previously Treated Pulmonary Tuberculosis (PTB) Patients on 8 Months Retreatment Regimen
  • Sputum smear exam should be repeated at month 3, after the patient receives the last dose of intensive-phase treatment
  • If sputum smear is positive at month 3, culture & DST should be done & repeat sputum smear exam is advised at month 5
  • If sputum smear is positive at month 5, culture & DST should be done & repeat sputum smear exam is advised at month 8
  • If sputum smear is positive at month 8, culture & DST should be done
  • Treatment failure is considered if MDR-TB is detected (smear- or culture-positivity) at any point; change of treatment is recommended
Possible Reasons for a Positive Sputum Smear at the End of Intensive Phase
  • Poor supervision & compliance of patient to the initial phase of therapy
  • Poor quality of anti-TB agents
  • Underdosage
  • Patient has extensive cavitation & heavy bacillary load that leads to slow resolution
  • Presence of comorbid conditions that interferes w/ treatment adherence or response
  • Presence of MDR-TB
  • Non-viable bacteria remains in microscopy

Managing Anti-Tuberculosis (TB) Drugs’ Side Effects

  • Patient who will have minor adverse effects is advised to continue the regimen & be given symptomatic treatment
  • Patient who will have major adverse effects is advised to discontinue the drug & be referred to a clinician/hospital for further evaluation & management

More Common Side Effects

  • Cutaneous reactions
    • Responsible drugs: Streptomycin, Isoniazid, Rifampicin, Pyrazinamide
    • For itching w/o rash & no other obvious cause: Give patient antihistamine, moisturizers & continue TB treatment while observing the patient
    • If rash develops: Discontinue all anti-TB drugs
      • Once resolved, anti-TB drugs should be re-introduced one by one at a lower dose & then gradually increased over 3 days
  • Deafness or dizziness or decreased urine output
    • Responsible drug: Streptomycin
    • Discontinue the drug
  • Drug-induced hepatitis
    • Responsible drugs: Isoniazid, Pyrazinamide, Rifampicin
      • Rifampicin can also cause asymptomatic jaundice w/o evidence of hepatitis
    • Discontinue all anti-TB drugs
    • If the patient is severely ill & unsafe to stop TB drugs, nonhepatotoxic agents (eg Streptomycin, Ethambutol & a fluoroquinolone) may be used
    • Once resolved, anti-TB drugs should be re-introduced one by one starting w/ Rifampicin & then Isoniazid after 3-7 days
      • If hepatitis w/ jaundice occurs during the intensive phase & then resolves, same drugs should be restarted but Pyrazinamide should be replaced w/ Streptomycin to complete the 2 months initial therapy followed by Rifampicin & Isoniazid for 6 months continuation therapy
      • If hepatitis w/ jaundice occurs during the continuation phase & then resolves, Isoniazid & Rifampicin should be restarted to complete the 4 months continuation therapy
  • Shock, purpura, acute renal failure
    • Responsible drug: Rifampicin
    • Discontinue the drug

Monitoring Multidrug-resistant Tuberculosis (MDR-TB) Patients

  • Close monitoring is important during treatment of MDR-TB patients
  • Sputum smear & culture should be done monthly until patient has smear & culture conversion (2 consecutive smears & cultures are negative)
  • After conversion, bacteriological monitoring is advised monthly for smears & quarterly for cultures
  • Monthly follow-up is advised until sputum conversion & then every 2-3 months thereafter
  • Weight should be recorded monthly
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